Spontaneous symmetry breaking in light cone quantum field theory
Abstract
We reexamine light cone quantisation of scalar field theories with a spontaneously broken internal symmetry. To this end we use the DiracBergmann algorithm for quantisation of constrained systems. Carefully taking into account the zero modes with light cone momentum k^{+} = 0, we obtain secondary constraints which determine the (tree level) vacuum structure of the theories. In 1 + 1 dimensions spontaneous symmetry breaking shows up in terms of a direct sum decomposition of the Hilbert space corresponding to the discrete phases of the theory. In 3 + 1 dimensions, when a continuous symmetry is spontaneously broken, one finds additional first class constraints corresponding to the broken group generators.
 Publication:

Physics Letters B
 Pub Date:
 November 1991
 DOI:
 10.1016/03702693(91)91011J
 Bibcode:
 1991PhLB..272...54H